AFP, BERLIN: Bayern Munich play Hoffenheim away on Saturday with the spotlight on whether out-of-favour Germany star Thomas Mueller plays for the defending Bundesliga champions.

The 27-year-old World Cup winner is struggling for a place in Bayern's starting line-up under Carlo Ancelotti, but impressed for Germany on Monday, creating two goals in a 6-0 rout of Norway in a World Cup qualifier.

Bayern resume after the international break in second place in the table on goal difference behind Borussia Dortmund, who face Freiburg away.

Dortmund, Bayern, Hamburg, who host RB Leipzig on Friday, and Hanover, who play Wolfsburg in a derby on Saturday, are the only teams with 100 percent records after the opening two rounds.

Mueller fumed on Bayern's bench when Carlo Ancelotti dropped him from the starting side in the 2-0 win at Werder Bremen a fortnight ago.

“I don't know what qualities exactly the coach wants to see from me,” moaned Mueller.

His frustration was clear after training with the first team in the build-up, only to be replaced by Thiago Alcantara in the starting lineup. By his own admission, Mueller struggled for form in the Bayern shirt in 2016/17, but Thiago blocks his path to the attacking midfield role behind striker Robert Lewandowski.

To compound Mueller's problems, new signing James Rodriguez is now back from injury and also battling for Bayern's Number 10 shirt.

With nine months to go before the World Cup, Mueller's plight has not gone unnoticed by the national team's hierarchy.

“I wish that someone in the club would say, “he must play” admitted Germany team manager Oliver Bierhoff.

But Bayern are taking a hard stance.

“No player has a guarantee of a regular place, it's not written in any contract, not even (Bayern captain) Manuel Neuer,” Bayern chairman Karl-Heinz Rummenigge told Sky.

“There is only one man who decides who plays -- the coach, Carlo Ancelotti.”

Bayern defender David Alaba is out with an ankle injury suffered while on international duty with Austria.

History is set to me made on Sunday when Bibiana Steinhaus becomes the first female referee in one of Europe's top leagues when she takes control of Hertha Berlin against Werder Bremen at Berlin's Olympic Stadium.

The 38-year-old police officer has been refereeing since 1999 and has officiated 81 matches in Germany's second tier since 2007.

Berlin boss Pal Dardai has said he will make a decision about whether Salomon Kalou faces Bremen with the 32-year-old having failed to score in his three Hertha games this season.

The Ivory Coast forward is just back from a two-legged World Cup qualifier against Gabon and has a habit of not playing well after returning from international duty.

“I will look deep in his eyes and know where he is ready to play on Sunday against Bremen or whether he is too tired,” said Dardai.